The present invention relates to a sealed container having a pressure-rupturable seal. When pressure is applied from inside the container, the seal preferentially ruptures in a well-defined path through the seal to permit controlled directional flow of the contents from the container.
In recent years, the popularity of “single-serve” beverage machines has been increasing. In the single-serve beverage machine, a predetermined amount of a beverage making ingredient, such as a liquid or solid concentrate/extract, is held in a container or capsule, which is placed into a beverage making apparatus. The apparatus then introduces water by injection into the container, where it dissolves, extracts, emulsifies, or dilutes the ingredient(s) to form a flavored beverage. The flavored beverage must then exit the container e.g. by flowing through an opening or perforation in the container.
Known single-serve beverage making systems are described, for example, in U.S. Pat. No. 5,325,765 (Sylvan et al); U.S. Pat. No. 5,840,189 (Sylvan et al); U.S. Pat. No. 6,142,063 (Beaulieu et al); U.S. Pat. No. 7,318,372 (Cooke); U.S. Pat. No. 6,698,333 (Halliday et al): U.S. Pat. No. 7,418,899 (Halliday et al); and EP-A-0821906 (Sara Lee), EP-A-0512468 (Nestle), EP-A-0468079 (Nestle), WO 94/01344 (Nestle), EP-A-0272922 (Kenco), and EP-A-0179641 (Mars) and WO 02/19875 (Mars), the entire contents of all of which are hereby incorporated herein by reference.
Containers for single-serve beverage machines may be made by thermoforming sheet or injection molding monolayer or multilayer polymeric resins to form relatively rigid plastic containers or capsules having at least one recessed cavity. A container may have a single recessed cavity or be internally divided into a plurality of recessed cavities. A liquid beverage making ingredient, e.g., a flavored syrup concentrate is placed into the cavity, and the container is closed by sealing a lid comprising e.g. a laminate of metallic foil and heat sealable plastic over the cavity.
During beverage making, the container top or bottom is pierced by a tubular inlet. The inlet tube introduces pressurized water and/or gas into the container which infuses with the beverage ingredient(s). The resulting pressurized mixture must then exit the container by rupturing through the seal between the lid and container. The problem with such containers is that the seal must be torn open to dispense the contents, which is often difficult and which often results in uncontrolled flow of the contents.
The improvement provided by this invention is a self-rupturing seal n such containers that is easily ruptured at a desired location by the application of pressure to the seal. When pressure is applied from inside the container, the seal preferentially ruptures in a well-defined path through the seal to permit controlled directional flow of the contents from the container.